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PCV Question

'79 US 244. Owned it for less than a year, so still figuring out its quirks. The (incomplete) service history from the previous owner showed that the flame trap was replaced in the early 2000s, so I figured it was overdue for an inspection. I popped the hood and (for the first time) noticed that the PCV system wasn't quite like the diagrams I had seen. Presumably, the flame trap was relocated for easier service. What was a little weirder was the apparent lack of an oil separator box. A tube comes out of the valve cover and goes straight into the flame trap housing. There are two hoses coming off of the flame trap housing. The smaller one goes to the intake manifold and the other to the air filter box. Nothing connecting to a separator box. Looking under the intake manifold, there does not appear to be a separator box. Is this normal for earlier 240s or did a previous owner remove the separator box?








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    PCV Question

    the setup you saw online didn't come in until 1981. the other thing that might need attention on the old setup is make sure the port on the intake for the small vacuum line is clear. i use an old hood cable cut down to about a foot to ream it out.








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    PCV Question

    That's the proper PCV system for your B21F. Be sure to make sure the rubber ring in the oil filler cap remains soft and fexible to make a good seal and not hardened and brittle. These often need replacing every year or two. Make sure the hose in the cap is also well seated. Check the bottom of the air filter more frequently to make sure it's not getting too oily, which can attract dust and start to reduce airflow.

    A good guess on your part, I'm impressed. There was indeed an aftermarket relocation kit from the likes of IPD to raise the flame trap for better accessibility. For an older engine, cleaning the flame trap element is often required and should be checked at every oil change, sighting through the holes for daylight. If it somehow happens to have the original layered copper style element (which were available as old stock from some aftermarket places until not that many years ago), they more easily get fouled and plug up with carbon, so should be replaced with the newer plastic style flame trap element with the holes that can be reemed out with a drill bit as needed. The plastic flame trap housing can become quite brittle from age and heat, so don't get carried away trying to get the element out for cleaning. If needed, clean it in place and rinse or blow out the debris. I usually finish with a rinse in paint solvent followed by drying.
    --
    Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now








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      PCV Question

      Thanks for the info. Glad to hear that is normal - all of the information I found online referred to the oil separator and I was afraid some previous owner had removed it. I was poking around the system a little yesterday. Flame trap is the later white plastic one and plenty of light comes through. I gave it a new air filter shortly after getting the car and didn't notice significant oil but I'll check up on the new one every so often. For what it's worth, relocation wasn't completely a guess on my part. I saw something about a relocation kit a while back and assumed that was what was going on.







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